AD 2020-22-07
Applicability
| Type | Manufacturer | Model | Details |
|---|---|---|---|
| aircraft | Bell Textron, Inc. | 412 | Airworthiness Directives; Bell Textron Inc. (Type Certificate Previously Held by Bell Helicopter Textron Inc.) Helicopters |
| aircraft | Bell Textron, Inc. | 412CF | Airworthiness Directives; Bell Textron Inc. (Type Certificate Previously Held by Bell Helicopter Textron Inc.) Helicopters |
| aircraft | Bell Textron, Inc. | 412EP | Airworthiness Directives; Bell Textron Inc. (Type Certificate Previously Held by Bell Helicopter Textron Inc.) Helicopters |
Unsafe Condition
excessive pylon pitch vibrations likely caused overload that resulted in cracked main gearbox (MGB) support case failures, and investigations are ongoing to determine the root cause of these vibrations.
AI-generated summary from the source AD text. Verify against the official source before acting.
Required Actions
revising Section 2, Normal Procedures, under both ``BEFORE TAKEOFF'' and ``IN-FLIGHT OPERATION(S)'' of the existing Rotorcraft Flight Manual (RFM) for your helicopter to add a caution about what to do if a sudden increase in one-per-rev vertical vibrations occurs with large steady state forward cyclic displacements in combination with collective input while at a certain RPM % is encountered while any part of the skids is touching the ground.
AI-generated summary from the source AD text. Verify against the official source before acting.
Compliance Time
Before further flight
AI-generated summary from the source AD text. Verify against the official source before acting.
Affected Aircraft
Bell Textron Inc. Model 412, 412CF, and 412EP helicopters
AI-generated summary from the source AD text. Verify against the official source before acting.
Federal Register Abstract
The FAA is adopting a new airworthiness directive (AD) for all Bell Textron Inc. (Type Certificate previously held by Bell Helicopter Textron Inc.) Model 412, 412CF, and 412EP helicopters. This AD requires revising the existing Rotorcraft Flight Manual (RFM) for your helicopter. This AD was prompted by an accident and multiple reports of a cracked main gearbox (MGB) support case. The FAA is issuing this AD to address the unsafe condition on these products.
Applicability Source Text
Show captured applicability text from the source AD
(c) Applicability
This airworthiness directive (AD) applies to Bell Textron Inc.
(Type Certificate previously held by Bell Helicopter Textron Inc.)
(Bell) Model 412, 412CF, and 412EP helicopters, certificated in any
category.
Note 1 to paragraph (c): Helicopters with a 412EPI or 412EPX
designation are Model 412EP helicopters.
Document Text
Show stored source text (verify against official source)
[Federal Register Volume 85, Number 213 (Tuesday, November 3, 2020)]
[Rules and Regulations]
[Pages 69485-69488]
From the Federal Register Online via the Government Publishing Office [<a href="http://www.gpo.gov">www.gpo.gov</a>]
[FR Doc No: 2020-24258]
=======================================================================
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DEPARTMENT OF TRANSPORTATION
Federal Aviation Administration
14 CFR Part 39
[Docket No. FAA-2020-0921; Project Identifier AD-2020-00323-R;
Amendment 39-21303; AD 2020-22-07]
RIN 2120-AA64
Airworthiness Directives; Bell Textron Inc. (Type Certificate
Previously Held by Bell Helicopter Textron Inc.) Helicopters
AGENCY: Federal Aviation Administration (FAA), DOT.
ACTION: Final rule; request for comments.
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SUMMARY: The FAA is adopting a new airworthiness directive (AD) for all
Bell Textron Inc. (Type Certificate previously held by Bell Helicopter
Textron Inc.) Model 412, 412CF, and 412EP helicopters. This AD requires
revising the existing Rotorcraft Flight Manual (RFM) for your
helicopter. This AD was prompted by an accident and multiple reports of
a cracked main gearbox (MGB) support case. The FAA is issuing this AD
to address the unsafe condition on these products.
DATES: This AD is effective November 18, 2020.
The Director of the Federal Register approved the incorporation by
reference of certain publications listed in this AD as of November 18,
2020.
The FAA must receive comments on this AD by December 18, 2020.
ADDRESSES: You may send comments, using the procedures found in 14 CFR
11.43 and 11.45, by any of the following methods:
<bullet> Federal eRulemaking Portal: Go to <a href="https://www.regulations.gov">https://www.regulations.gov</a>. Follow the instructions for submitting comments.
<bullet> Fax: 202-493-2251.
<bullet> Mail: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE, Washington, DC 20590.
<bullet> Hand Delivery: U.S. Department of Transportation, Docket
Operations, M-30, West Building Ground Floor, Room W12-140, 1200 New
Jersey Avenue SE, Washington, DC 20590, between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays.
For service information identified in this final rule, contact Bell
Textron, Inc., P.O. Box 482, Fort Worth, TX 76101; telephone 817-280-
3391; fax 817-280-6466; or at <a href="https://www.bellcustomer.com">https://www.bellcustomer.com</a>. You may
view this service information at the FAA, Office of the Regional
Counsel, Southwest Region, 10101 Hillwood Pkwy., Room 6N-321, Fort
Worth, TX 76177. For information on the availability of this material
at the FAA, call 817-222-5110. It is also available on the internet at
<a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No.
FAA-2020-0921.
Examining the AD Docket
You may examine the AD docket on the internet at <a href="https://www.regulations.gov">https://www.regulations.gov</a> by searching for and locating Docket No. FAA-2020-
0921; or in person at Docket Operations between 9 a.m. and 5 p.m.,
Monday through Friday, except Federal holidays. The AD docket contains
this final rule, any service information that is incorporated by
reference, any comments received, and other information. The street
address for the Docket Operations is listed above. Comments will be
available in the AD docket shortly after receipt.
FOR FURTHER INFORMATION CONTACT: Kuethe Harmon, Safety Management
Program Manager, DSCO Branch, Compliance & Airworthiness Division, FAA,
10101 Hillwood Pkwy., Fort Worth, TX 76177; telephone 817-222- 5198;
email <a href="/cdn-cgi/l/email-protection#92f9e7f7e6faf7bcfaf3e0fffdfcd2f4f3f3bcf5fde4"><span class="__cf_email__" data-cfemail="1d76687869757833757c6f7072735d7b7c7c337a726b">[email protected]</span></a>.
SUPPLEMENTARY INFORMATION:
Discussion
The FAA is adopting a new AD for Bell Textron Inc. Model 412,
412CF, and 412EP helicopters. This AD was prompted by an accident on a
Model 412EP helicopter and multiple reports of a cracked MGB support
case. Initial investigations showed that excessive pylon pitch
vibrations likely caused overload that resulted in these failures, and
investigations are ongoing to determine the root cause of these
vibrations. However, field experience and flight test data indicate
that excessive degradation of the transmission mounts and friction
dampers could cause the sudden increase in one-per-rev vertical
vibration, and minimum collective and cyclic controls friction not
meeting the maintenance manual specifications may also be a
contributing factor.
This condition, if not addressed, could result in structural
failure of the MGB support case and subsequent reduced control of the
helicopter. To address this unsafe condition, this AD requires revising
Section 2, Normal Procedures, under both ``BEFORE TAKEOFF'' and ``IN-
FLIGHT OPERATION(S)'' of the existing RFM for your helicopter.
Related Service Information Under 1 CFR Part 51
The FAA reviewed Section 2--Normal Procedures, of Bell 412 BHT-412-
FM-1 RFM, Revision 26; Bell 412 BHT-412-FM-2 RFM, Revision 13; Bell 412
BHT-412-FM-3 RFM, Revision 20; Bell 412EP BHT-412-FM-4 RFM, Revision
37; Bell 412EPI BHT-412-FM-5 RFM, Revision 9; and Subaru Bell 412EPX
BHT-412-FM-6 RFM, Revision 5, each dated August 19, 2020. These RFM
revisions add a caution under ``BEFORE TAKEOFF'' and ``IN-FLIGHT
OPERATION(S)'' to the existing RFM for your helicopter.
This service information is reasonably available because the
interested parties have access to it through their normal course of
business or by the means identified in the ADDRESSES section.
Other Related Service Information
The FAA also reviewed Bell Operation Safety Notice 412-18-43, dated
December 19, 2018 (OSN), which notified Model 412 and 412EP helicopter
owners and operators of reports regarding rapid buildup of one-per-rev
vertical vibration associated with a large steady state forward cyclic
displacement in combination with collective input while at 100/103
percent revolutions per minute (RPM) with any part of the skid gear in
contact with the ground. The OSN also noted that this vibration mode
can be encountered on all Bell Model 412 helicopters equipped with any
type of landing gear. Finally, the OSN reminded operators that, should
this vibration mode be experienced, the amount of forward cyclic input
shall immediately be reduced and, if necessary, the collective and
rotor RPM shall also be reduced to exit the vibration mode described.
FAA's Determination
The FAA is issuing this AD after evaluating all of the relevant
information and determining the unsafe condition described previously
is likely
[[Page 69486]]
to exist or develop in other helicopters of these same type designs.
AD Requirements
This AD requires, before further flight, revising Section 2, Normal
Procedures, under both ``BEFORE TAKEOFF'' and ``IN-FLIGHT
OPERATION(S)'' of the existing RFM for your helicopter to add a caution
about what to do if a sudden increase in one-per-rev vertical
vibrations occurs with large steady state forward cycle displacements
in combination with collective input while at a certain RPM % is
encountered while any part of the skids is touching the ground. The
caution varies depending on your helicopter model and serial number.
Revising the existing RFM for your helicopter may be performed by
the owner/operator (pilot) holding at least a private pilot
certificate. This authorization is an exception to the FAA's standard
maintenance regulations. The pilot must record compliance with this AD
in the aircraft maintenance records in accordance with 14 CFR
43.9(a)(1) through (4) and 14 CFR 91.417(a)(2)(v). The record must be
maintained as required by 14 CFR 91.417, 121.380, or 135.439.
Interim Action
The FAA considers this AD interim action. If final action is later
identified, the FAA might consider further rulemaking then.
FAA's Justification and Determination of the Effective Date
Section 553(b)(3)(B) of the Administrative Procedure Act (5 U.S.C.)
authorizes agencies to dispense with notice and comment procedures for
rules when the agency, for ``good cause'' finds that those procedures
are ``impracticable, unnecessary, or contrary to the public interest.''
Under this section, an agency, upon finding good cause, may issue a
final rule without seeking comment prior to the rulemaking.
An unsafe condition exists that requires the immediate adoption of
this AD without providing an opportunity for public comments prior to
adoption. The FAA has found that the risk to the flying public
justifies waiving notice and comment prior to adoption of this rule
because the required corrective action must be completed before further
flight. Therefore, notice and opportunity for prior public comment are
impracticable and contrary to public interest pursuant to 5 U.S.C.
553(b)(3)(B). In addition, for the reasons stated above, the FAA finds
that good cause exists pursuant to 5 U.S.C. 553(d) for making this
amendment effective in less than one month.
Comments Invited
This AD is a final rule that involves requirements affecting flight
safety, and the FAA did not provide you with notice and an opportunity
to provide your comments prior to it becoming effective. However, the
FAA invites you to participate in this rulemaking by submitting written
comments, data, or views. The most helpful comments reference a
specific portion of the AD, explain the reason for any recommended
change, and include supporting data. To ensure the docket does not
contain duplicate comments, commenters should send only one copy of
written comments, or if comments are filed electronically, commenters
should submit them only one time.
Except for Confidential Business Information (CBI) as described in
the following paragraph, and other information as described in 14 CFR
11.35, the FAA will file in the docket all comments received, as well
as a report summarizing each substantive public contact with FAA
personnel concerning this rulemaking during the comment period. The FAA
will consider all the comments received and may conduct additional
rulemaking based on those comments.
Confidential Business Information
CBI is commercial or financial information that is both customarily
and actually treated as private by its owner. Under the Freedom of
Information Act (FOIA) (5 U.S.C. 552), CBI is exempt from public
disclosure. If your comments responsive to this final rule contain
commercial or financial information that is customarily treated as
private, that you actually treat as private, and that is relevant or
responsive to this final rule, it is important that you clearly
designate the submitted comments as CBI. Please mark each page of your
submission containing CBI as ``PROPIN.'' The FAA will treat such marked
submissions as confidential under the FOIA, and they will not be placed
in the public docket of this final rule. Submissions containing CBI
should be sent to Kuethe Harmon, Safety Management Program Manager,
DSCO Branch, Compliance & Airworthiness Division, FAA, 10101 Hillwood
Pkwy., Fort Worth, TX 76177; telephone 817-222- 5198; email
<a href="/cdn-cgi/l/email-protection#254e5040514d400b4d4457484a4b654344440b424a53"><span class="__cf_email__" data-cfemail="12796777667a773c7a73607f7d7c527473733c757d64">[email protected]</span></a>. Any commentary that the FAA receives which is
not specifically designated as CBI will be placed in the public docket
for this rulemaking.
Regulatory Flexibility Act
The requirements of the Regulatory Flexibility Act (RFA) do not
apply when an agency finds good cause pursuant to 5 U.S.C. 553 to adopt
a rule without prior notice and comment. Because FAA has determined
that it has good cause to adopt this rule without notice and comment,
RFA analysis is not required.
Costs of Compliance
The FAA estimates that this AD affects 96 helicopters of U.S.
registry. Labor rates are estimated at $85 per work-hour. Based on
these numbers, the FAA estimates that operators may incur the following
costs in order to comply with this AD.
For Model 412 and 412EP helicopters, revising the existing RFM for
your helicopter takes about 0.5 work-hour for an estimated cost of $43
per helicopter and $4,128 for the U.S. fleet.
For Model 412CF helicopters, there are no costs of compliance
associated with this AD because there are no helicopters with this type
certificate on the U.S. Registry.
Authority for This Rulemaking
Title 49 of the United States Code specifies the FAA's authority to
issue rules on aviation safety. Subtitle I, section 106, describes the
authority of the FAA Administrator. Subtitle VII: Aviation Programs
describes in more detail the scope of the Agency's authority.
The FAA is issuing this rulemaking under the authority described in
Subtitle VII, Part A, Subpart III, Section 44701: General requirements.
Under that section, Congress charges the FAA with promoting safe flight
of civil aircraft in air commerce by prescribing regulations for
practices, methods, and procedures the Administrator finds necessary
for safety in air commerce. This regulation is within the scope of that
authority because it addresses an unsafe condition that is likely to
exist or develop on products identified in this rulemaking action.
Regulatory Findings
This AD will not have federalism implications under Executive Order
13132. This AD will not have a substantial direct effect on the States,
on the relationship between the national government and the States, or
on the distribution of power and responsibilities among the various
levels of government.
For the reasons discussed above, I certify that this AD:
(1) Is not a ``significant regulatory action'' under Executive
Order 12866, and
[[Page 69487]]
(2) Will not affect intrastate aviation in Alaska.
List of Subjects in 14 CFR Part 39
Air transportation, Aircraft, Aviation safety, Incorporation by
reference, Safety.
Adoption of the Amendment
Accordingly, under the authority delegated to me by the
Administrator, the FAA amends 14 CFR part 39 as follows:
PART 39--AIRWORTHINESS DIRECTIVES
0
1. The authority citation for part 39 continues to read as follows:
Authority: 49 U.S.C. 106(g), 40113, 44701.
Sec. 39.13 Amended]
0
2. The FAA amends Sec. 39.13 by adding the following new airworthiness
directive:
2020-22-07 Bell Textron Inc. (Type Certificate Previously Held by
Bell Helicopter Textron Inc.): Amendment 39-21303; Docket No. FAA-
2020-0921; Project Identifier AD-2020-00323-R.
(a) Effective Date
This AD is effective November 18, 2020.
(b) Affected ADs
None.
(c) Applicability
This airworthiness directive (AD) applies to Bell Textron Inc.
(Type Certificate previously held by Bell Helicopter Textron Inc.)
(Bell) Model 412, 412CF, and 412EP helicopters, certificated in any
category.
Note 1 to paragraph (c): Helicopters with a 412EPI or 412EPX
designation are Model 412EP helicopters.
(d) Subject
Joint Aircraft System Component (JASC): 5400, Nacelle/Pylon
Structure.
(e) Unsafe Condition
This AD was prompted by an accident and multiple reports of a
cracked main gearbox (MGB) support case. The FAA is issuing this AD
to address excessive pylon pitch vibrations. The unsafe condition,
if not addressed, could result in structural failure of the MGB
support case and subsequent reduced control of the helicopter.
(f) Compliance
Comply with this AD within the compliance times specified,
unless already done.
(g) Required Actions
Before further flight:
(1) For Bell Model 412 helicopters with serial number (S/N)
33001 through 33107 inclusive, S/N 33108 through 33213 inclusive, S/
N 34001 through 34024 inclusive, or S/N 36001 through 36019
inclusive, revise Section 2, Normal Procedures, under both ``BEFORE
TAKEOFF'' and ``IN-FLIGHT OPERATION(S)'' of the existing Rotorcraft
Flight Manual (RFM) for your helicopter by adding the information in
Figure 1 to paragraph (g)(1) of this AD or by adding this
information under both ``BEFORE TAKEOFF'' and ``IN-FLIGHT
OPERATION(S)'' of the following as applicable for your helicopter:
Bell 412 BHT-412-FM-1 RFM, Revision 26; or Bell 412 BHT-412-FM-2
RFM, Revision 13, each dated August 19, 2020. Using a different
document with information identical to this information under both
``BEFORE TAKEOFF'' and ``IN-FLIGHT OPERATION(S)'' in the RFM
revision specified in this paragraph for your helicopter is
acceptable for compliance with the requirements of this paragraph.
[GRAPHIC] [TIFF OMITTED] TR03NO20.033
(2) For Bell Model 412 helicopters with S/N 36020 through 36086
inclusive, and for Bell Model 412EP helicopters with S/N 36087
through 36999 inclusive, S/N 37002 through 37999 inclusive, S/N
38001 through 38999 inclusive, or S/N 39101 through 39999, revise
Section 2, Normal Procedures, under both ``BEFORE TAKEOFF'' and
``IN-FLIGHT OPERATIONS'' of the existing RFM for your helicopter by
adding the information in Figure 2 to paragraph (g)(2) of this AD or
by adding this information under both ``BEFORE TAKEOFF'' and ``IN-
FLIGHT OPERATIONS'' of the following as applicable for your
helicopter: Bell 412 BHT-412-FM-3 RFM, Revision 20; Bell 412EP BHT-
412-FM-4 RFM, Revision 37; Bell 412EPI BHT-412-FM-5 RFM, Revision 9;
or Subaru Bell 412EPX BHT-412-FM-6 RFM, Revision 5, each dated
August 19, 2020. Using a different document with information
identical to this information under both ``BEFORE TAKEOFF'' and
``IN-FLIGHT OPERATIONS'' in the RFM revision specified in this
paragraph for your helicopter is acceptable for compliance with the
requirements of this paragraph.
[[Page 69488]]
[GRAPHIC] [TIFF OMITTED] TR03NO20.034
(3) For Bell Model 412CF helicopters, revise Section 2, Normal
Procedures, under both ``BEFORE TAKEOFF'' and ``IN-FLIGHT
OPERATIONS'' of the existing RFM for your helicopter by adding the
information in Figure 1 to paragraph (g)(1) of this AD. Using a
different document with information identical to that contained in
Figure 1 to paragraph (g)(1) of this AD is acceptable for compliance
with the requirements of this paragraph.
(4) The actions required by paragraphs (g)(1) through (3) of
this AD may be performed by the owner/operator (pilot) holding at
least a private pilot certificate and must be entered into the
aircraft records showing compliance with this AD in accordance with
14 CFR 43.9(a)(1) through (4) and 14 CFR 91.417(a)(2)(v). The record
must be maintained as required by 14 CFR 91.417, 121.380, or
135.439.
(h) Alternative Methods of Compliance (AMOCs)
(1) The Manager, DSCO Branch, FAA, has the authority to approve
AMOCs for this AD, if requested using the procedures found in 14 CFR
39.19. In accordance with 14 CFR 39.19, send your request to your
principal inspector or local Flight Standards District Office, as
appropriate. If sending information directly to the manager of the
certification office, send it to the attention of the person
identified in paragraph (i) of this AD. Information may be emailed
to: <a href="/cdn-cgi/l/email-protection#d6effb978581fbe7efe6fb95998596b0b7b7f8b1b9a0"><span class="__cf_email__" data-cfemail="586175190b0f75696168751b170b183e3939763f372e">[email protected]</span></a>.
(2) Before using any approved AMOC, notify your appropriate
principal inspector, or lacking a principal inspector, the manager
of the local flight standards district office/certificate holding
district office.
(i) Related Information
For more information about this AD, contact Kuethe Harmon,
Safety Management Program Manager, DSCO Branch, Compliance &
Airworthiness Division, FAA, 10101 Hillwood Pkwy., Fort Worth, TX
76177; telephone 817-222-5198; email <a href="/cdn-cgi/l/email-protection#d7bca2b2a3bfb2f9bfb6a5bab8b997b1b6b6f9b0b8a1"><span class="__cf_email__" data-cfemail="f59e8090819d90db9d9487989a9bb5939494db929a83">[email protected]</span></a>.
(j) Material Incorporated by Reference
(1) The Director of the Federal Register approved the
incorporation by reference (IBR) of the service information listed
in this paragraph under 5 U.S.C. 552(a) and 1 CFR part 51.
(2) You must use this service information as applicable to do
the actions required by this AD, unless the AD specifies otherwise.
(i) Section 2, Normal Procedures, of Bell 412 BHT-412-FM-1
Rotorcraft Flight Manual (RFM), Revision 26, dated August 19, 2020.
(ii) Section 2, Normal Procedures, of Bell 412 BHT-412-FM-2 RFM,
Revision 13, dated August 19, 2020.
(iii) Section 2, Normal Procedures, of Bell 412 BHT-412-FM-3
RFM, Revision 20, dated August 19, 2020.
(iv) Section 2, Normal Procedures, of Bell 412EP BHT-412-FM-4
RFM, Revision 37, dated August 19, 2020.
(v) Section 2, Normal Procedures, of Bell 412EPI BHT-412-FM-5
RFM, Revision 9, dated August 19, 2020.
(vi) Section 2, Normal Procedures, of Subaru Bell 412EPX BHT-
412-FM-6 RFM, Revision 5, dated August 19, 2020.
(3) For service information identified in this AD, contact Bell
Textron, Inc., P.O. Box 482, Fort Worth, TX 76101; telephone 817-
280-3391; fax 817-280-6466; or at <a href="https://www.bellcustomer.com">https://www.bellcustomer.com</a>.
(4) You may view this service information at the FAA, Office of
the Regional Counsel, Southwest Region, 10101 Hillwood Pkwy., Room
6N-321, Fort Worth, TX 76177. For information on the availability of
this material at the FAA, call 817-222-5110.
(5) You may view this service information that is incorporated
by reference at the National Archives and Records Administration
(NARA). For information on the availability of this material at
NARA, email <a href="/cdn-cgi/l/email-protection#244241405641430a4841434548644a4556450a434b52"><span class="__cf_email__" data-cfemail="9bfdfeffe9fefcb5f7fefcfaf7dbf5fae9fab5fcf4ed">[email protected]</span></a>, or go to: <a href="https://www.archives.gov/federal-register/cfr/ibr-locations.html">https://www.archives.gov/federal-register/cfr/ibr-locations.html</a>.
Issued on October 15, 2020.
Gaetano A. Sciortino,
Deputy Director for Strategic Initiatives, Compliance & Airworthiness
Division, Aircraft Certification Service.
[FR Doc. 2020-24258 Filed 11-2-20; 8:45 am]
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